This is a longitudinal study aimed at identifying the early antecedents of antisocial behavior. Two samples of Manhattan children, one a random sample (N equals 1034) and the other a Welfare sample (N equals 1000) selected randomly from four Welfare centers were drawn in 1965. An initial interview (Time 1) and a follow up interview five years later (Time 2) were conducted with the mother. Continuous school records and cumulative police records were collected, and a subsample of the children was directly interviewed in late adolescence. For the cross-sectional sample measures of antisocial behavior were constructed separately from survey reported and from police recorded information. A significant and substantial amount of the variance in each of the measures has been explained and the differential predictors of police recorded and survey reported antisocial behavior have been identified. Further, certain measures which draw on survey as well as police reported information have been developed. In progress is the prediction of "types of delinquent behavior" as well as the construction of a two tier predictive model identifying familial risk, later adding child specific behavior. The analysis of antisocial behavior in the Welfare sample is planned for the coming year.